Two Rare Complications in One Patient: Acquired von Willebrand Syndrome Associated with Intracranial Plasmacytoma.

Here, we describe a rare case of acquired von Willebrand syndrome (VWS) associated with intracranial plasmacytoma. The literature includes reports of a few cases of plasmacytoma with central nervous involvement, but none of them with acquired VWS. Diagnosis was made based on a stereotaxic intracerebral biopsy. During this biopsy, a ventriculoperitoneal shunt was established, which was complicated with abnormal bleeding. Subsequent hemostasis assessment related to hemopathy revealed acquired von Willebrand disease. The patient received induction therapy with bortezomib, thalidomide, and dexamethasone (VTD), followed by high-dose melphalan chemotherapy and autologous stem cell transplantation, and then VTD consolidation, and finally maintenance with lenalidomide. Our patient currently remains in very good partial response without neurological symptoms after 4 months of maintenance. The patient is free of progression 14 months after their original presentation.

Idelalisib in a patient with refractory Waldenström's macroglobulinemia complicated by anuric renal failure: a case report.

BACKGROUND: Waldenström's macroglobulinemia is a rare B-cell lymphoma. The gold standard treatment for Waldenström's macroglobulinemia is an anti-CD20 antibody (rituximab) in combination with alkylating agents and dexamethasone. Treatment targeting the B-cell receptor such as ibrutinib (but not idelalisib) is currently approved for treatment of patients with relapsed or refractory Waldenström's macroglobulinemia. CASE PRESENTATION: We report a case of a 71-year-old white French man with Waldenström's macroglobulinemia who presented with acute renal failure and hyperviscosity syndrome. His Waldenström's macroglobulinemia was refractory to first-line treatment with rituximab, cyclophosphamide, and dexamethasone. Because of his hemorrhagic syndrome and medical history of recent myocardial infarction, we decided to treat him with idelalisib 150 mg twice daily instead of ibrutinib. We observed a very quick improvement in the patient's clinical status without need for dose adjustment. CONCLUSION: Our patient's case provides the first evidence, to the best of our knowledge, that idelalisib may be an efficient treatment option for patients with Waldenström's macroglobulinemia complicated by anuric renal failure and in whom ibrutinib is contraindicated.

Hodgkin Lymphoma and Castleman Disease: When One Blood Disease Can Hide Another.

We describe a rare case of Castleman disease associated de novo with Hodgkin lymphoma. The incidence of Castleman disease is rare; only a few studies have described it in de novo association with Hodgkin lymphoma. The patient described here complained of unique evolutionary axillary adenopathy. A positron-emission tomography/computed tomography scan revealed hypermetabolic activity in this area. Diagnosis was based on a total excision biopsy of the adenopathy. The patient underwent complete remission with ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) chemotherapy for treating Hodgkin lymphoma after surgical excision of the unicentric Castleman disease lesion.

Studies on the substrate specificity of the DNA methylase activity from Escherichia coli K-12.

A partially purified extract of DNA methylases from E. coli K-12 containing DNA-adenine as well as DNA-cytosine methylase activities has been examined with respect to different DNA species as substrates. The results show that the natural content of 6-MAP) in the applied DNA represses the DNA-adenine methylase activity. On the other hand, 5-MC, already present in the substrate does not influence the activity of the DNA-cytosine methylase. DNA from Micrococcus radiodurans, which is completely free of methylated bases served as comparison. Since netropsin preferentially binds to AT-rich regions of DNA, the influence of this oligopeptide antibiotic on the methylation of DNA was investigated. As expected the antibiotic predominantly inhibits adenine methylation of DNA. The degree of inhibition depends on the molar ratio of netropsin to DNA phosphate.